Drilling equipment



April 27, 1954 H. L. JOHNSON DRILLING EQUIPMENT 2 Sheets-Sheet 1 Filed June 22, 1949 INVENTOR HOWARD L. JOHNSON April 27, 1954 H. L. JOHNSON DRILLING EQUIPMENT 2 Sheets-Sheet 2 Filed June 22, 949

1N VENTOR HOWARD 1 JOHNSON Patented Apr. 27, 1954 UNITED STATES PATENT OFFICE 1'21 Claims.

This invention relates to drilling equipment for forming bores. such as those of oil wells, ,thru the floor of a body of water such as the ocean.

It is well known that oil bearing strata underlie bodies of water just the same as they underlie the adjacent dry land. This is particularly true of the continental, shelf area of western North America, the Gulf of Mexico, the Persian Gulf, etc.

Hitherto exploitation of such submerged oil deposits has been limited to slanting drill lines out from shore or else drilling from a. rigidly anchored. base vertically located over the oil field. Such operations have been by sinking a drilling barge or caisson on the floor of shallow Water and then drilling from within the caisson, or from the surface. of the water, or from above the water if the sunken structure extends up this far. Or a floating barge is anchored to the bottom by pilings so as to form what. amounts to an artificial island. All of these methods are necessarily limited to use in calm and shallow water, and in addition involve great expense.

Now by the present invention there is provided means for vertically drilling thru that portion of the earth or ocean floor which is covered by any depth of water. Drilling is effected from a floating barge, temporarily anchored against substantial lateral displacement I but vertically oscillatable with the swell in con trast to previous drilling barges. Whereas previous equipment required drilling from a rigid base because it employed a rigid drill stem, I use a segmented drill stem which is convertable at will between rigid and flexible forms: under pressure from the drilling head my stem is rigid and rotatable as a unit, when drilling is interrupted, the segments are separable so as to transform the drilling line into a completelyflexible one, the rigid segments being longitudinally aligned at all times Within a flexible conduit.

Since the drill stem is not laterally supported thru the depth of water, anchoring and guide means are provided for the drill stem and bit at the bottom of the water. These means comprise a sinkable barge, separable for refloating into two or more. parts along a guide channel which receives the drill stem and bit therethru. The sunken barge is maneuverable on. the ocean floor from the floating barge so as to direct the drill bit at any desired angle as it pierces the ocean bottom; the sunken barge is also provided with.

indicating means for conveying to.- the surface operator, information of the precise angular position of the guide channel.

In. this manner, drilling is no longer limited to the comparatively shallow depths in which a diver or sand hog could work (for limited periods) or to the extent to which piling could be used to support av rig for drilling from above the surface of the water. In addition, drilling is no longer limited to calm water, since my flexible drill line can be disconnected at the top, and the floating barge temporarily removed upon the imminence of a period. of severe storms such as the monsoons. The freed end of the drill line is dropped to the bottom of the ocean in an arc to avoid the upper choppy zone of water, and later picked up and. drilling continued after a storm. This of course would be impossible with arigid drill line.

Aside from the marine equipment, certain features of my invention, in particular the segmented drill stem, can also be used to advantage in land based: drilling.

Additional advantages will become apparent as the description proceeds.

In the drawings which form part of the present. specification;

Fig. l is an elevational view of the floating drill rig, the sinkable barge shown in operative position on. the ocean. floor, and the anchoring member showing the drill line in broken lines in inoperative position;

Fig. 2 is a perspective view of a collapsible grappling hook adapted. for separating the segments of Fig. 7 within. the flexible conduit;

Figs. 3 and 4 are. perspective views of the two halves of the sunken barge shown broken apart for refloating;

Fig. 5 is an elevational view, with portions broken away. of the operating structures connected. to the upper end of the drill line on the floating. barge;

Fig. 6 is an elevational view partly in vertical sectional a turbo drill operatively connected to the lower end of the drill line;

Fig. 7 is a perspective view, partly in vertical section, of my flexible drill line;

Fig. 8 is a similar view of my flexible drill line showing a modified form of connectible segments.

therein;

Fig. 9 is a similar view of my flexible drill line showing yet another form of interlocking segments disposed within the outer conduit;

Fig. 10 is an elevational view of the locking mechanism of the barge segment of Fig. 3;

Fig. 11 is a horizontal sectional view taken through the interlocking means which holds together the two portions of the sunken barge of Fig. 1;

Fig. 12 is an elevational view of mechanism within the sunken barge for indicating and al tering the angular position of its central guide channel;

Fig. 13 is a top plan view showing a bank of photocells arranged to observe the position of a spirit level within the sunken barge as seen along the line l3-l3 of Fig. 12;

Fig. 14 is a schematic showing of electrical circuits and mechanisms for correlating the rotational position of the sunken barge with a surface indicator;

Fig. 15 is a schematic lower face view of a concave bowl or supporting structure showing the manner of radial arrangement of photocells across the surface; and

Figure 16 is an elevational view, partly in vertical section of a freely swingable pendulum within the sunken barge, showing a brake therefor and carrying a light and lens at its upper end for indicating its swing or rest position to the photocells of Fig. 15 which latter structure is disposed generally horizontally thereabove.

There is here illustrated a floating drilling rig or ship 20 which is provided with such equipment as a derrick 22, engine 24, winch 26, pumps 28 for providing compressed air and circulating drilling fluid or mud thru the drill line 30 to the drill bit 32. Air pressure is used both for applyin down-pressure to the drill stem and bit and for blowing water out of the sinkable barge 34 upon refloating. The drill rig together with the sinkable barge are moved to the location where a submarine well is desired, and the former is then secured by anchor lines 36 against lateral displacement over the place where seismic or other exploratory methods have indicated the presence of a geological structure likely to contain petroleum.

The sinkable barge 34 is formed of two outwardly similar parts 34a, 34b each having buoyancy chambers which can be pumped or blown out by lines 38, from surface equipment. The barge has a generally hemispherical bottom covered by spikes 4B for engaging the ocean floor, the two parts a and b being separable along a generally vertical line which bisects an upright guide channel 42 formed jointly by the adjacent end walls 44, 46. Accordingly the sunken barge can be broken apart along the refloated, leaving the drill line 30 (or the outer flexible conduit thereof) in place after the bit 32 has been driven to the desired depth, and withdrawn.

The drill bit 32 is connected to the drill line 30 and laced in the guide channel 42 before the barge is sunk, the two parts thereof 34a and 34b being held together by a series of horizontally oscillatable bolts 48 in part b which are extended into corresponding sockets 50 (Figure 11) in part a and held by a vertically slidable, metal plate 52 (Figure 10) disposed in a guide way 54 of part I), being cut-out at apertures 56 thru which the enlarged head 58 of each bolt may be inserted when the plate is in its Up position. The plate being then depressed to locking position (Figure 11), the portions 66 of the slidin plate are disposed along opposite sides of the neck 62 of the bolt and against the rear face of the protruded head 58 so as to prevent its withdrawal from the socket 50. Within the barge part 34b, the neck 48 of the bolt is connected to a coil spring 54 tensioned to withdraw it from the socket 50 in the adjacent barge part 34a.

The sliding plate 52 or at least the upper end guide channel 42 and ,1;

thereof being formed of rust resistant iron, it can be raised to release the bolts 48 and thus break apart the two parts of the barge, by means or" a magnet or electromagnet (not shown) lowered from the surface vessel, or by an electromagnet built in the barge 34a and energised by a current from the floating barge 20. An elevated circular railing is located about the flat top 68 of the complementary parts of the sinkable barge, above which top the severable guide channel 42 may extend in a peripherally enlarged guard portion 10. When employing a drill line 30 of less diameter than the guide channel 2. an axially split, detachable spacing collar 12 is located within the channel between the barge portions 34a and 34b, and the drill line 30.

The drill line 30 is composed of an outer flexible conduit 14 having disposed therein a series of longitudinally aligned, separable tubular segments l6, triangular (or other polygonal form) in cross section, with downwardly restricted, tapered walls so that the lower end of one segment will nest or fit snugly within the top of the segment immediately below. If desired, the base of the upper socket of a segment may be provided with an abutment ledge 18 discontinuous at the corners. It will be observed that the length of each segment is greater than the inner diameter of the conduit so that upon the segments 16 being separated from each other therein, they cannot become inverted but remain longitudinally aligned. When the segments are separated, the whole line 30 is thus flexible, but upon the outer conduit 14 being held upright, and down pres- 0 sure applied to the inner string of separated segments 16, the latter will join together as above described to form a rigid drill stem which may be rotated as a unit, within the conduit, from the floating platform 20 so as to operate the drill bit 32 below the sunken barge. At the same time, drilling fluid or mud may be circulated to the bottom of the bore in the customary manner, pumped down thru the aperture 80 of the tubular drill stem and out thru or around the bit, thence back to the surface carrying the cuttings by moving thru the space 82 between the outside of the connected segments 16 and the inside of the outer conduit 14.

A modified form of segment construction is shown in Figure 9, wherein the longitudinally apertured body of the segment 84 may be cylindrical in shape, with its respective ends formed as a triangular socket 86 and a correspondingly shaped, engaging stud 88 projecting upward from an abutment ledge 90 and adapted to be received within the socket when the flat end 92 of the upper segment is pressed upon the abutment ledge of the lower segment. Again, in such position the segmented drill stem may be rotated as a rigid unit under down-pressure, with fluid circulated thru its length to the bit. If desired, a removable pin 91 may be inserted thru the aligned apertures BI, 93 to lock the segments against longitudinal separation.

Still another form of which is rotatable within the is illustrated in Figure 8, in lengths 94, 95 of the tube being screw threadedly connected, similar to conventional practice. However, there is additionally provided on the male end of the segment 94, a loose fitting slidable collar 95 located in a peripherally restricted recess 98 and slidable between opposing terminal abutments I00 and I02 thereof. At several points,

segmented drill stem, flexible conduit 14 this case adjacent ber I22 and dropped to the ocean 'ure 1) some distance from the sunken barge 3k.

acre-gar pled pipe segments can have their adjacent ends.

separated: by the distance required to. give the desired flexibility to-theseparated drill stem within the flexible conduit N. The lower edge oi" the collar 96 is formed with generally axially and conicall-y directed teeth I06 adapted to friction ally engage a correspondin series of teeth or sockets I08 around the upper ed e of the Sement shoulder I02. Accordingly, the upper segment 94; can be unscrewedfrom. the lowcr'seg ment while remaining within the. conduit 1:4 and drawn upso asto mutually engage or lookthe: complementary teeth I06: and 08;- furtherrota tion of the upper segment 94 thereupon rotates the lower one 95 in unison soas to unscrew the latter from the similarly connected segment lmmedi'ately below it. This process is eifected'from the drilling platform 20 for each joint which it'- is desired to unscrew. The segments: may be re;- coupled within the conduit by merely reversing the direction of rotation. It will be observed that with this construction of drill stem with threaded segments, it does not require a continuous down-pressur from the drilling platform to keep the segments united, altho of cours it: may still be desirable to transmit pressure insuch manner to the bit.

Whilerotation of the segmented drill stem within the conduit flior'thepurpose of imparting corresponding motion to a rotary drill bit: of either the fish tail type 32 or a rock bit has: just been emphasized, it should be apparent that the drill line 30 can also be employed without rotation, for drilling with a (Figure 6) by circulation at opening (86) thereto. I

In the turbo drill (Figure 6) the upper end of the shell I I is threadedly or otherwise at tached to the bottom of the non-rotating drl l-l stem, and the bit (not shown) is "secured at the other end to the rotating tube 1 I 2, thru each of which the drilling fluid passes to the bottom of the bore. Moving fluid forced down (by the surface pump) thru the rotor 'IIA of thethydraulic turbine, propels the drive shaft H6 which is coupled to sealed reduction gears H 8 the drive tube the reduction in turn transmit the movement to I I2, the fluid traveling around gears which operate in oil. l

When for any reason such as the imminence of a period of rough weather, it is desired: to

temporarily remove the drilling rig before" drilling is completed, after. separation of the seg ments 16, 84 or 94 within that length of the; conduit (iuwhich extends. thru the watar the, upper end of the conduit may be: closedlbyija cap I20 which is attached toa weighted menibottom (Figf- The upper end of the drill line is thus removed from the region of thesea which is sub ject to violent agitation by surface winds or storms and is carried'down to the bottom "in the form of an arc I24 which may be readily-engaged by a grappling hook from above and drawn to the surface when drilling is. to be resumed. If desired,.part or all of the drilling fluid within the line' ill]v may be removed, before capping so that. the air whiahieplaues it'ivill promote the. continued elevation. of. the ar turbine type drill I 1 air pressure upon beneath the-water rather than leaving it tall:

laterally:

On the floating platform 20, rotation of the segmented drill stem (1-6:, 84 or 94) may be effected by the conventional rotary table I26 thru the square central; correspondingly shaped grief stem or kelly I28 suspended from: a swivel [:30 thru. which the mud line Ir32 supplies drilling fluid into the kel-ly for transmission to the segmented drill stem. Within the derrick 22', from a lower or traveling pulley block I34 there is hung a tubular air chamber I130: within which a reciprocable. piston I38 is Slidingly disposed, attached at its lower face to a. piston stem I40 which in tum is: connected to the; swivel I 30. Compressed air supplied to the upper part of the cylinder [36 thru the line M2: .from the compressor 28 serves to exert. a predetermined. constant down.

thrust or pressure on the piston I38 and thence thru, the kclly and drill stem so as to cushion the vertical oscillations the. ocean swell. Thus upon an up thrust. of the floating platform around the grief stem, the the piston I38 will still hold the segments of the drill stem locked together. Upon a down thrust of the floating rig, consequent up movement of the kelly thru. the rotary table I26" will be cushioned by the air in the chamber I36.

The pulley lines I44 are connected at their upper extremity to a: conventional crown block (not shown.) at the head of the derrick 22 and the line. I46 therefrom to the: Winch 26 may be set to respond automatically (by known means) to changes from. a predetermined tension so asto raise. the block I31 and cylinder I36 upon upthrust of the piston I38,v and lower them again upon slacking '0f. tension on the line (caused by dropping of the boat: into a trough of the swell).

It will be seen, that the direction at which the drill bit. 32' and drill stem enter the earth will be a continuation of the direction of theguide channel 42h Accordingly it is desirable both. to know at what angle this guide channel lies, as well as to be able to alter its direction bymovementv 01 the sunken barge 34. Thus, the barge may bedroppe'd on'aslopingsea-t bottom thru. which it is desired. to direct a vertical bore;- or the barge may come to rest on a hat surface and. it may be desired to start a slanted bore therefrom. In either event. it must first be -de-; termined at whatangle the channel is slanted from the perpendicular and in what direction the deviation lies. For this purpose, the means of Figures 11-13 are. provided.-

Within one or both halvesof the sunken barge. a any-wheel. luismountedfon a horizontal axle I50 for rotation incither dircctiqn by;-a quiche starting, reversible motor I52, the assembly be ing supported on-a platform 1.54 by uprights i56, I58. The whole platform assembly in turn. may be rotated by a reversible motor I60, acting. thru reduction gears 16!, on a vertical axle I 62, the motor I being secured to the barge structure I63. Intelligence and control of the angular position of the. sunken barge 34 is eiiected by means of a pair of synchronised motors Itk-Ififi. respectively within the lowered horse and on the surface .vessel 20,. and electrically connected as shown. While the barge is descending, a gyroscope. I 6.5 connected to the rotor o imotor [6.4, prevents. 'rotationthereofvwhile allowing move mer t of, the. statorwith twisting ofthje barge aperture of which extends a.

of the boat caused by body in sinking. Accordingly, when a line current is imposed at L1, L2, the rotor in the surface motor I66 will assume the same position with respect to its stator that the rotor and stator of the lower motor I64 occupy. Movement of the upper rotor will turn the connected indicator I61 and thus show the directional heading of the barge on the bottom. Or in other words, parallel when both were at the surface of the water, the indicator I61 will now show the amount and direction which the barge 34 has rotated on its vertical axis in sinking. Since the original directional heading of the flywheel I48 at the surface was known, its change of position which is identical with the changed position of the barge-is also known.

Also mounted on the horizontal platform I54 I68 disposed between a light tube I and a bank of photocells I12. Position of the air bubble I14 along the level is shown by the particular photocell immediately adjacent thereto, due to transmission of a different amount of light from the lamp I10 thru thebubble than thru the surrounding liquid. Since the directional heading of the flywheel I48 is known, as just described, the same is known for the spirit level I68 since they are both mounted on the same platform I54 which remains stationary with respect to the barge as the latter descends. Accordingly, it is now known whether or not the barge has landed in a horizontal position or not, as well as the direction in which the flywheel and spirit level are aligned. If the barge is not level, the platform I54 can be rotated 1 thru 360 by the motor I60, using the lower selsyn I64 as a pilot motor therefor, controlled from the surface motor I66, stopping to take readings of the spirit level I68 at intermediate points thru the 360. In this manner it is learned in what direction the guide channel 42 slants and to what extent.

Accordingly, that the sunken desired to right until the flywheel I48 points in this direction and the flywheel is then given a number of quick spins so as to roll the barge by this amount on its spiked bottom, aided if desired by slightly lifting the barge from the surface by 38. Or if the barge lands with its top horizontal and it is desired to tilt it in a certain direction by a specified amount, the same process is followed: the flywheel I48 is turned in this direction and rotated so as position, and the water in the several buoyancy chambers of the barge is then balanced so as to keep the barge steady at the new position. The platform I54 carrying the spirit level I68 and aligned photocells I12 can again berota't'ed to if it is determined, for example, barge lists 3 SSW, and it is show on the surface indicator (not shown) connected to the photocells, the new inclination of the barge.

The selsyn-type system comprising the paired motors I64, I66 is based upon an instrument which is mechanically a miniature bipolar, rotating field, three phase alternator. The rotor is wound with a single-phase concentrated winding; the stator, with a three-circuit distributed Y-connected winding. Electrically, in normal operation, the device acts as a transformer and voltages and currents existing in the instrument are all single-phase. The rotor windings R1, R2 are excited from an alternating voltage source; By transformer action, voltages are induced in assuming the two rotors were it, the platform I54 is turned its cables to tip the barge to this the three elements of the stator winding, the magnitude depending upon the angular position of the rotor. Assuming both rotors free to turn, they will take such a position that the voltages induced in the two stators are of balanced magnitude and displacement. Under this condition of stator-voltage balance between the two instruments there is no circulating current in the stator windings. Now if the rotor of one device is displaced by a certain angle and the rotor of the other remains in its original position, the statorvoltage balance is altered and a circulating current will flow in the windings. This circulating current reacting on the excitation flux provides a torque tending to turn the rotors of the machines to a position where the induced stat0rvoltages are again equal and opposite. Thus, with one rotor unrestrained, any motion given to the other rotor will be transmitted to and duplicated by the first rotor.

Another method of determining the position of the sunken barge is illustrated in Figures 12-13. Within the barge, a pendulum I16 is suspended by a ball and socket mounting I'lB about which there are disposed brake means I60 operable from the surface vessel for engaging the pendulum stem I82 so as to prevent its swinging while the barge is having its position changed. Above the mounting socket, the stern carries an electric light I84 within itself and a converging lens I86 at its tip. Above the pendulum, with its lower annular edge disposed parallel to the mounting support I88 is a concave structural member I90 carrying on its under, arcuate face, photocells arranged on axial lines radiating from the center I92 thereof, which center is directly above the normal rest position of the pendulum when the support I88 1s horizontal (i. e. the guide channel 42 is vertical). The dished surface of the support I90 describes an arc radiating from the center of the ball and socket mounting I18. The photocells are connected to a similarly arranged indicating device (not shown) on the surface vessel and a surface directional indicator I61 is connected to the photocell support I80 and gyroscope I by synchronised motors I64, I66 as just described.

Accordingly, when the barge comes to rest, the brakes I are withdrawn and the light I84 turned on. The swinging light being focused to a point by the lens I86, only those photocells along its path will transmit an impulse to the surface, so that by a straight line drawn thru the farthermost cells, the direction and extent of swing will be seen immediately, from which its midor rest-point will be evident. From this, knowing the rotational heading of the barge, its inclination will be realized. In place of the photocells of Figure 12, an iconoscope could be substituted to convey the swing of the pendulum to a cathode ray oscilloscope at the surface, similar to television transmission between camera and station receiver. Or photographs of the pendulum could be made in the barge and transmitted to the surface.

When the segments of the drill stem are not positively connected together for lifting each other by raising the upper one, as in Figure 8, the drill bit is joined to the drilling table by a cable (not shown) extending thru the segment aperture 80, so that thus raising the bit within the bore or flexible conduit 14 will automatically pull up all the intervening segments of the drill stem. However, when it is desired only to lift the segments 16 starting at an interrne diate point in the drill stem, this be done by dropping a three prcna upw rdly slanted, collapsible grappling hook I94 (Figure 2) down the ap rture 80 to the desired level and then raising it. The outswlmg arms 196 then engage the bottom corners of a segment 16 from beneath so as to slide or lift it out of the retaining socket of the immediately dependent segment, socket. By thus temporarily separating the segmen-tsat any point, they can be removed merel from the flexible conduit 3:0, if desired; or in this manner side wall samples, for example-can be taken at any :level in the bore without removing tiled-rill bit. After the raisedsegments have been dropped back into place, the arms [-9.6 are gathered about the shank I98 by the lines 200 from the surface, and the grappling hook is withdrawn from the drill stem.

While I have shown and described in some detail a presently preferred embodiment of "my drilling equipment, it is to be understoodthat various modifications may be made inthe construction and operation thereof within the spirit and scope of the subsequently claimed invention which it is my intention to claim broadly within the limitations imposed by the prior art.

"Certain subject matter herein disclosed claimed in my copendin'g application iSer. No. 122,295.

'11. A separable, multiple-se ment submarine vessel {adapted to be sunk and to rest inatpredetermined-position on the bottom of 1a ibo'dyof water; buoyancy-"chambers within the vessel adapted to float each segment thereof separately; a generally vertical guide channel formed along the line of separation of said segment and adapted to receive therein a longitudinally displaceable drill stem and a conduit surrounding said stem; means for detachably holding said segments together on said bottom; means carried by said vessel for measuring and transmitting its inclination and rotational position to receiving instruments at the surface of the water; and means carried by said vessel and operable from the surface of the water for adjusting the inclination of the sunken vessel to a desired position whereby said guide channel may be directed at a predetermined angle for drilling thru the bottom of the body of water by operation of said drill stem from the surface.

2. The vessel of claim 1 wherein the bottom thereof is substantially convex in all directions and carries projections for engagement with the bottom of said body of water.

3. The vessel of claim 1 wherein said measuring means comprise a spirit level having a longitudinal series of photocells in alignment therewith for determining the position of the entrapped gas bubble alsong said level; and means for jointly rotating the level and photocells a predetermined amount about an upstanding axis.

4. The vessel of claim 1 wherein said means for adjusting the inclination comprise a generally upright flywheel disposed within the vessel and rotatable in either direction on a transverse axle; and means for jointly rotating said flywheel and transverse axle about an upstanding axis.

5. In combination with a sinkable vessel, the improvement comprising: walls defining at least two segments of the vessel separable along an upright line, th walls along said line being complementarily recessed to define a generally vertical guide channel therebetween adapted to re- 10 cei e therein a longitudinally :displaceable drill stem and a conduit surrounding said stem; buoy ancy chambers within the vessel adapted to float each segment thereof Separately; and means for detachably holding said segments together when sunk- 6. In combination with .a sunken guide structure supported upon the earth beneath a body of water, and earth boring tools operated through the body of Water and traversing said guide structure to form a bore in the submerged earth beneath the structure, the improvement comprising; .a flexible conduit extending from the mouth of the bore through said guide structure to the surfaceof the water, laterall unsupported along most of its len th and enclosing therein a drill stem adapted to operate a drill bit in the :bore viitcun a vessel floating .on the surface of the water. In combination with a surface vessel and "earth boring tools operated therefrom in a submarine bore, the improvement comprisin a s'inkable'vessel having wallsdefining at least two buoyant segments separable along an upright line, the walls along said line being complementarily recessed to define a generally vertical guide channel therebetween, and a longitudinally displ able dr ll stem and a on u t surrou din said stem disposed said uide ch n and exfloated while leaving the conduit in the mouth of thebore. I

' "8; In combination with a surfac vessel and earth boring tools operated therefrom in a submarine bore, the improvement comprising: a sinkabie vessel having walls defining at least two buoyant segments separable along an upright line, the walls along said line being complementarily recessed to define a generally vertical guide channel therebetween, a flexible conduit extending from the guide channel to the surface vessel and a drill stem disposed in said conduit and comprising a plurality of longitudinally aligned segments individually having a thrust-engagement socket formed at one end and having the other end correspondingly'shaped so as to be insertable within the socket of the adjacent segment whereby a drill bit may be operated in a submarine bore from the surface vessel by the drill stem within said conduit, and the sunken vessel may be separated along said guide channel and the segments refloated While leaving the conduit in the mouth of the bore.

9. The method of earth boring beneath a body of water from the surface thereof, which method comprises: anchoring the lower end of a flexible conduit by insertion of same into the earth underlying said water; supporting said conduit at its upper end so the conduit extends substantially upright thru the water; forming a submarine bore by suspending a drill stem and attached drill bit down said conduit from said upper end and operating same from the surface; discontinuing drilling and withdrawing the portion of said drill stem which is within the water-surrounded section of the flexible conduit; capping the upper end of said conduit with a removable closure member; and dropping said capped end into the body of water at a point of lateral displacement from the lower anchored end thereof, from which position it may be subsequently raised to resume 1 1 drilling, upon reinsertion oi the Withdrawn drill stem.

10. The method of earth boring beneath a body of water from the surface thereof, which method comprises: anchoring the lower end of a flexible conduit by insertion of same into the earth underlying said water; supporting said conduit at its upper end so the conduit extends substantially upright thru the water; forming a submarine bore by suspending a segmented drill stem and attached drill bit down said conduit from said other end and operating same from the surface; discontinuing drilling and separating the portion of said drill stem which is within the watersurrounded section of the flexible conduit; capping the upper end of said conduit with a removable closure member; and dropping said capped end into the body of water at a point of lateral displacement from the lower anchored end thereof, from which position it may be subsequently raised to resume drilling, upon reassembly of the drill stem within said conduit.

11. The method of earth boring beneath a body of water, which method comprises: sinking to the bottom of said water a vessel having a generally vertical guide channel formed therein and anchoring one end of a flexible conduit by insertion of same into the earth underlying said water, said conduit extending through said guide channel; supporting said conduit at its upper end so the conduit extends substantially upright through the water laterally unsupported along most of its length; forming a submarine bore by suspending a drill stem and attached drill bit down said conduit from said upper end and operating same; and then removing said sunken vessel while leaving the lower end of said conduit anchored in the bore.

12. The method of forming a well beneath a body of water, which method comprises: anchoring the lower end of a flexible conduit by insertion of same into the earth underlying said water; supporting said conduit at its upper end so the conduit extends substantially upright through the water; forming a submarine bore by operation of earth boring tools within said conduit from said upper end; discontinuing drilling and removing said tools; sealing said flexible conduit against entrance of water and allowing same to rest on the bottom of the water.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 222,690 Goldschmidt Dec. 16, 1879 2,187,871 Voorhees Jan. 23, 1940 2,217,879 Willey Oct. 15, 1940 2,281,717 Pyeatt May 5, 1942 2,336,338 Zublin Dec. 7, 1943 2,360,361 Mountbatten Oct. 17, 1944 2,464,911 White Mar. 22, 1949 2,467,113 Deiters Apr. 12, 1949 2,475,933 Woolslayer et al. July 12, 1949 2,476,309 Lang July 19, 1949 2,480,144 Laycock Aug. 30, 1949 2,503,423 Silverman et al. Apr. 11, 1950 2,503,516 Shrewsbury Apr. 11, 1950 2,512,783 Tucker June 27, 1950 

